config/ompi_ext: use mpi module in mpi_ext module

If MPI extensions are enabled, all
`ompi/mpiext/pcollreq/use-mpi/mpiext_*_usempi.h` are included in
`ompi/mpi/fortran/mpiext-use-mpi/mpi-ext-module.F90` and all
`ompi/mpiext/pcollreq/use-mpi/mpiext_*_usempif08.h` are included in
`ompi/mpi/fortran/mpiext-use-mpi-f08/mpi-f08-ext-module.F90` using
`#include` directives.

In `mpiext_*_usempi.h` and `mpiext_*_usempif08.h`, some MPI extension
may want to use constants or handles defined in the `mpi` module and
the `mpi_f08` module. For example, if you want to define a new
datatype in `mpi_f08_ext`, you'll need the definition of
`type(mpi_datatype)`. However, putting `use mpi_f08` line in thier
`mpiext_*_usempif08.h` may cause a compilation error if more than
one MPI extensions are enabled because the `use` statement must be
put prior to any variable declarations.

To resolve this problem, this commit puts `use mpi` and `use mpi_f08`
as first lines of `mpi-ext-module.F90` and `mpi-f08-ext-module.F90`
respectively.

Signed-off-by: KAWASHIMA Takahiro <t-kawashima@jp.fujitsu.com>

config/ompi_ext.m4

@@ -171,6 +171,9 @@ EOF
 #include "ompi/mpi/fortran/configure-fortran-output.h"
 
 module mpi_ext
+!     Some mpi_ext extensions may require the mpi module.
+      use mpi
+!
 !     Even though this is not a useful parameter (cannot be used as a
 !     preprocessor catch) define it to keep the linker from complaining
 !     during the build.
@@ -213,6 +216,9 @@ EOF
 #include "ompi/mpi/fortran/configure-fortran-output.h"
 
 module mpi_f08_ext
+!     Some mpi_f08_ext extensions may require the mpi_f08 module.
+      use mpi_f08
+!
 !     Even though this is not a useful parameter (cannot be used as a
 !     preprocessor catch) define it to keep the linker from complaining
 !     during the build.

ompi/mpi/fortran/mpiext-use-mpi-f08/Makefile.am

@@ -22,6 +22,7 @@ if OMPI_BUILD_FORTRAN_USEMPI_OR_USEMPIF08_EXT
 AM_FCFLAGS = -I$(top_builddir)/ompi/include -I$(top_srcdir)/ompi/include \
              $(OMPI_FC_MODULE_FLAG)$(top_builddir)/ompi/mpi/fortran/base \
              $(OMPI_FC_MODULE_FLAG)$(top_builddir)/ompi/mpi/fortran/use-mpi-f08/mod \
+             $(OMPI_FC_MODULE_FLAG)$(top_builddir)/ompi/mpi/fortran/use-mpi-f08 \
              -I$(top_srcdir) $(FCFLAGS_f90)
 
 flibs =

ompi/mpi/fortran/mpiext-use-mpi/Makefile.am

@@ -21,6 +21,7 @@ if OMPI_BUILD_FORTRAN_USEMPI_OR_USEMPIF08_EXT
 
 AM_FCFLAGS = -I$(top_builddir)/ompi/include -I$(top_srcdir)/ompi/include \
              $(OMPI_FC_MODULE_FLAG)$(top_builddir)/ompi/mpi/fortran/base \
+             $(OMPI_FC_MODULE_FLAG)$(top_builddir)/ompi/mpi/fortran/use-mpi-ignore-tkr \
              -I$(top_srcdir) $(FCFLAGS_f90)
 
 flibs =